Blisters When You Walk Higher Miles. Walking 10 miles (over 3 hours), even if you are used to walking for six miles, is more of a challenge. You can do it, but most people are likely to develop blisters in new places. Shoes and gear that worked fine for two hours may not be ideal for four hours.
How the Aurora Borealis occur. The Northern Lights are caused by the interaction of the solar wind - a stream of charged particles escaping the Sun - and our planet's magnetic field and atmosphere.
As with many natural phenomena, the Northern Lights are unpredictable and it's hard to say with any scientific certainty when the best time to see them is. Technically, they're 'on' all year round, it's just that the summer sun makes them invisible from about April until August.